Delayed-accelerated hyperfractionated radiation therapy for advanced-stage or high-risk rhabdomyosarcoma

The treatment of six patients with advanced-stage or high-risk rhabdomyosarcoma (RMS) is described. These patients were treated with a delayed-accelerated hyperfractionated radiation therapy (DAHFRT) regimen which delivers 5200 cGy over 20 treatment days. Acceptable early toxicity was noted when radiation therapy was given after a full course of chemotherapy and major attempts at resection of the primary tumor. The DAHFRT regimen has inherent biological and time-intensity advantages compared to other fractionation schemes which may be exploited to improve local control. The DAHFRT regimen should be considered as an alternate fractionation scheme for RMS patients and a possible foundation from which dose-escalation of radiation therapy may be attempted using advanced treatment planning technology. Late effects of high-dose radiation therapy, although a major concern, should assume less priority given the high local failure rates of advanced-stage patients and the advent of conformed radiation therapy treatment planning and delivery which can be used to reduce treatment-related toxicity.